.TH std::basic_string_view::find 3 "2024.06.10" "http://cppreference.com" "C++ Standard Libary"
.SH NAME
std::basic_string_view::find \- std::basic_string_view::find

.SH Synopsis
   constexpr size_type find( basic_string_view v, size_type pos = 0 ) \fB(1)\fP \fI(since C++17)\fP
   const noexcept;
   constexpr size_type find( CharT ch, size_type pos = 0 ) const      \fB(2)\fP \fI(since C++17)\fP
   noexcept;
   constexpr size_type find( const CharT* s, size_type pos, size_type \fB(3)\fP \fI(since C++17)\fP
   count ) const;
   constexpr size_type find( const CharT* s, size_type pos = 0 )      \fB(4)\fP \fI(since C++17)\fP
   const;

   Finds the first substring equal to the given character sequence.

   1) Finds the first occurence of v in this view, starting at position pos.
   2) Equivalent to find(basic_string_view(std::addressof(ch), 1), pos).
   3) Equivalent to find(basic_string_view(s, count), pos).
   4) Equivalent to find(basic_string_view(s), pos).

.SH Parameters

   v     - view to search for
   pos   - position at which to start the search
   count - length of substring to search for
   s     - pointer to a character string to search for
   ch    - character to search for

.SH Return value

   Position of the first character of the found substring, or npos if no such substring
   is found.

.SH Complexity

   O(size() * v.size()) at worst.

.SH Example


// Run this code

 #include <string_view>

 int main()
 {
     using namespace std::literals;

     constexpr auto str{" long long int;"sv};

     static_assert(
         1 == str.find("long"sv)            && "<- find(v , pos = 0)" &&
         6 == str.find("long"sv, 2)         && "<- find(v , pos = 2)" &&
         0 == str.find(' ')                 && "<- find(ch, pos = 0)" &&
         2 == str.find('o', 1)              && "<- find(ch, pos = 1)" &&
         2 == str.find("on")                && "<- find(s , pos = 0)" &&
         6 == str.find("long double", 5, 4) && "<- find(s , pos = 5, count = 4)"
     );

     static_assert(str.npos == str.find("float"));
 }

.SH See also

   rfind             find the last occurrence of a substring
                     \fI(public member function)\fP
   find_first_of     find first occurrence of characters
                     \fI(public member function)\fP
   find_last_of      find last occurrence of characters
                     \fI(public member function)\fP
   find_first_not_of find first absence of characters
                     \fI(public member function)\fP
   find_last_not_of  find last absence of characters
                     \fI(public member function)\fP
                     finds the first occurrence of the given substring
   find              \fI\fI(public member\fP function of\fP
                     std::basic_string<CharT,Traits,Allocator>)
